Avoiding and Treating Mosquito Bites

This 4th of July weekend, while you're barbecuing, swimming—pretty much doing everything they do in those active-lifestyle tampon and Boniva commercials—remember, the sun isn't the only thing you need to avoid. After a recent hike left our arms covered in mosquito bites, we asked dermatologist Jeannette Graf what we should know for next time:

Concentrate on concentrations: "A repellent with five percent Deet will give you about an hour and a half of protection. One with 25 percent, five hours of protection. If you're swimming or sweating a lot, you will have to reapply more frequently."

Go natural: "Skin is an organ of absorption, so I prefer to use natural formulas containing citronella oil, which is registered as a bug repellent with the EPA, and offers similar protection to Deet. (Even chemical bug repellents don't kill bugs; they just make you unattractive for feeding.) There are a lot of good citronella repellents out there; I like Burt's Bees Herbal Insect Repellent and California Baby Natural Bug Blend."

Don't scratch: "The best thing you can do for a bug bite is stop the itch. Scratching will only make it worse. An anti-itch lotion like Sarna or Aveeno Anti-Itch Concentrated Lotion can be very helpful—and cortisone cream, either over-the-counter or prescribed by a dermatologist, is probably the most effective."

Know thyself: "Some people react quickly and severely to mosquito bites—if you're one of them, you probably know it. If you're going to be camping or in another situation where it seems likely that you'll be bitten, take a Claritin or a non-sedating antihistamine ahead of time to minimize your reaction. You could also see your dermatologist about getting a prescription cortisone cream to take with you, so you can treat bites right away."

Ask for help: "If the bite seems to be lasting a long time, if the itch is driving you crazy, or if there's any question that your bite is really a bite—see a dermatologist."